# Representing Volume

My fourth graders are starting a new unit on fraction computation this week.  Last week, students finished up month long unit on volume and area.  After grading the tests, I started to reflect on a few different activities that seemed to help students understand volume a bit better.  One particular task will be highlighted in this post. I’m not going to lie, this task was quite challenging for kids, but I feel like the students were able to make some amazing math connections in the process.

So last week, I brought the students to the front of the room and we discussed area and volume.  Students provided examples of area and volume and referenced the city that they created earlier in the year.  Students then randomly came up to the room and drew out a slip of a paper.  The slips indicated a particular volume task. The tasks were all related to making a 3D shape that matched a certain dimension range.

Students drew the small little sheets out of a cup.  It was exciting as students weren’t quite sure which sheet they were going to get.  Students were then given the direction sheet, where they were asked to create the net, tape/glue it together, place it on the sheet, and then take a picture and send it to their digital portfolio.

Students were then given the centimeter grid and were off to the races.  Some students had to take multiple grid sheets as they missed the required dimensions on many different attempts.  Eventually, most students calculate the volume that they needed and used a formula.  Students then used the formula to calculate the volume before creating the net.

Students didn’t seem to have too many problems with rectangular prisms or cubes, but cylinders and cones were a bit more challenging.  Students were able to create the base fairly quickly.  The curved surface was an issue for some.  Many students had trouble creating a large enough curved surface to match the cones and cylinders.  One student mentioned that the curved surface needed to be around 3 1/4 of the length of the circumference.  I enjoyed hearing that as a couple students had a conversation on how to make their shape fit a required dimension. That’s an #eduwin in my book.  Students then attached their constructed structures to the direction sheet.

Students then put the different structures on a map and created a small city.  I’m hoping at some point the students will be able to create a short stop-motion-video using the volume structures.  It might fit in perfectly with our rate/ratio unit that will be coming up after PARCC testing.

## Author: Matt Coaty

I've taught elementary students for the past 14 years. I enjoy reading educational research and learning from my PLN. Words on this blog are my own.